Certain dibenzopyranones are useful pharmacological agents. It recently has been found that trans-1-hydroxy-3-alkyl-6,6-dimethyl-6,6a,7,8,10,10a-hexahydro-9H-dibenzo[ b,d]pyran-9-ones are especially useful in the treatment of pain, anxiety, and depression, see U.S. Pat. Nos. 3,928,598, 3,994,673, and 3,953,603. Such compounds can be prepared, according to the disclosure by Fahrenholtz, Lurie and Kierstead, J. Am. Chem. Soc. 88, 2079(1966), 89, 5934(1967), by reacting a 5-alkyl resorcinol with diethyl .alpha.-acetylglutarate to form an ethyl 4-methyl-5-hydroxy-7- 6,6-dimethyl-6,6a,7,8,10,10a-hexahydro-9H-dibenzo[b,d]pyran-9-one is the subject of Day and Lavagnino's copending application filed this even date herewith.
An object of this invention is to provide an alternate process for preparing substantially exclusively cis-hexahydrodibenzo[b,d]pyran-9-ones, utilizing novel compounds which are ketals of 4-(1-hydroxy-1-methylethyl)-3-cyclohexen-1-one.